New South Wales commissioned this work in early 2020 as part of a review of the approach to Air Quality Index (AQI) reporting. Historically, many jurisdictions in Australia have approached AQI calculation for particulate matter (PM) using 24-hour average concentration data, and in particular 24-hour rolling average values in near real-time AQI reporting, to align with the 24-hour national standards. Recent large-scale air pollution events have highlighted that the use of 24-hour (rolling) average PM data restricts the ability to provide more up-to-date air quality data and information that the public needs.
This review report describes how various agencies locally and internationally use short-term averaged particulate matter concentrations (e.g. 1-hour) when calculating AQIs. Further, the broader approach to air quality reporting is documented, including aspects such as AQI categories used for public health messaging. The review found that currently there is no consensus on how particulate matter pollution should be calculated and reported. The report may be used by agencies with responsibilities on air quality reporting, to determine how best to formulate an approach that includes the use of highly time-resolved Air Quality Index calculations and timely public notification protocols during air pollution events.
